Abstract. Biomass burning (BB) is the second largest source of
trace gases and the largest source of primary fine carbonaceous particles in
the global troposphere. Many recent BB studies have provided new emission
factor (EF) measurements. This is especially true for non-methane organic
compounds (NMOC), which influence secondary organic aerosol (SOA) and ozone
formation. New EF should improve regional to global BB emissions estimates
and therefore, the input for atmospheric models. In this work we present an
up-to-date, comprehensive tabulation of EF for known pyrogenic species based
on measurements made in smoke that has cooled to ambient temperature, but
not yet undergone significant photochemical processing. All EFs are
converted to one standard form (g compound emitted per kg dry biomass
burned) using the carbon mass balance method and they are categorized into
14 fuel or vegetation types. Biomass burning terminology is defined to
promote consistency. We compile a large number of measurements of biomass
consumption per unit area for important fire types and summarize several
recent estimates of global biomass consumption by the major types of biomass
burning. Post emission processes are discussed to provide a context for the
emission factor concept within overall atmospheric chemistry and also
highlight the potential for rapid changes relative to the scale of some
models or remote sensing products. Recent work shows that individual biomass
fires emit significantly more gas-phase NMOC than previously thought and
that including additional NMOC can improve photochemical model performance.
A detailed global estimate suggests that BB emits at least 400 Tg yr−1
of gas-phase NMOC, which is almost 3 times larger than most previous
estimates. Selected recent results (e.g. measurements of HONO and the BB
tracers HCN and CH3CN) are highlighted and key areas requiring future
research are briefly discussed.